This doctrine logically follows from the doctrine of unconditional election, but perhaps a better name would be “particular redemption”.  What it signifies is this: If Christ chose those to be saved before the foundation of the world, then it follows that he gave his life on the cross for those same elect ones—his chosen ones—those particular people– and this is indeed, what the bible teaches.
While the atonement of Christ is sufficient for the sins of the whole world, it is efficient only for those who trust in it, so that the saving effectiveness of the atonement that Jesus accomplished is limited to those for whom that saving effect was prepared before the foundations of the world. Said simply, Christ actually accomplished on the cross what he intended to: the atonement of the elect, those chosen in Him before the foundation of the world. He did not just make their atonement possible.
Please see the following Scriptures:Â Ephesians 5.25; Matthew 20.28; John 10.15; John 10.26; John 17.9; John 17.19
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